Method of manufacturing plano lens

Abstract

Disclosed is a method of accurately, simply forming a light absorbing layer for improving contrast in a transmission screen including micro glass beads two-dimensionally arranged. A light absorbing layer made from toner is formed on glass beads held in a transparent adhesive layer up to a thickness sufficient to cover the glass beads. The light absorbing layer is irradiated with parallel rays of light in the direction from a transparent substrate, to melt and remove only a portion of the light absorbing layer positioned over a light outgoing portion of each glass bead by the energy of the rays of light converged through the glass bead. By suitably selecting a material of the light absorbing layer, openings can be formed in the light absorbing layer by means of combustion, sublimation or ablation due to the energy of the converged rays of light. Further, a light absorbing layer having each opening positioned only over a light outgoing portion of each glass bead can be formed by making use of a photosensitive material.

Dependencies are inferred from the claim text.